Prisma: truncate before seeding.

seed.ts

import { PrismaClient } from '@prisma/client'
const prisma = new PrismaClient()

async function main() {

  // Get all table names from the information_schema
  const result: { table_name: string }[] = await prisma.$queryRaw`
    SELECT table_name
    FROM information_schema.tables
    WHERE table_schema = 'public' AND table_type = 'BASE TABLE';
  `;

  // Truncate them all in one combined query
  await prisma.$queryRawUnsafe(
    `TRUNCATE TABLE ${result.map(({ table_name }) => `"${table_name}"`).join(", ")} RESTART IDENTITY CASCADE`,
  );
}

main()
  .then(async () => {
    await prisma.$disconnect()
  })
  .catch(async (e) => {
    console.error(e)
    await prisma.$disconnect()
    process.exit(1)
  })